Antibiotic Silver Particles Coated Graphene Oxide/polyurethane Nanocomposites Foams and Its Mechanical Properties

Silver nanoparticles(AgNPs) are widely adopted in polyurethane foams(PUFs) as a type of antibacterial agent. However, due to its poor interfacial interaction, Ag NPs are difficult to be dispersed in the polymer matrix uniformly, which deteriorates the enhancement effect. In this paper, silver-coated graphene nanocomposite(Ag/GO) is prepared by an enzyme reductant which is efficient and non-toxic. Compared with traditional antibacterial agent, the Ag/GO nanoparticles can be uniformly dispersed in...     

β-二亚胺配体支持的铝胺化合物的制备及其催化ε-己内酯开环聚合的高效性能

成功合成了由β-二亚胺配体(L)支持的铝胺化合物(L)AlH(NMe2)2(L=HC(C(Me)NAr)2,Ar=2,6-iPr2C6H3)(1)。该化合物采用分步合成法进行制备,以n-BuLi与HNMe2反应生成的锂盐LiNMe2作为前驱体,进一步与(L)AlH2溶液共混通过消除LiH得到目标产物。通过核磁共振谱、元素分析、红外漫反射光谱和X射线单晶衍射确定了铝胺化合物(L)AlH(NMe2)2的组成与结构。该铝胺化合物中,金属Al中心同时形成Al-H和Al-NMe2基团,在催化ε-己内酯的开环聚合的反应中展现出了优异的催化活性。通过高效凝胶渗透色谱测定了所得聚合物的分子量和分子量分布。     

Exploring the entanglement of free spin-(1/2), spin-1 and spin-2 fields

In this study, we explore the entanglement of free spin-(1/2), spin-1, and spin-2 fields. We start with an example involving Majorana fields in 1+1 and 2+1 dimensions. Subsequently, we perform the Bogoliubov transformation and express the vacuum state with a particle pair state in the configuration space, which is used to calculate the entropy. This clearly demonstrates that the entanglement entropy originates from the particles across the boundary.Finally, we generalize this method to free spin-1 and spin-2 fields. These higher free massless spin fields have wellknown complications owing to gauge redundancy. We deal with the redundancy by gauge-fixing in the light-cone gauge. We show that this gauge provides a natural tensor product structure in the Hilbert space, while surrendering explicit Lorentz invariance. We also use the Bogoliubov transformation to calculate the entropy. The area law emerges naturally by this method.     

在大学物理实验课程中创新人才培养的研究与实践

为培养创新人才,推进大学物理实验课程的教学改革,探索出一条以多层次实验教学体系为主体、以创新研究型教学模式为手段、以科技竞赛创新基地建设为外延的培养创新人才的新途径,使大学物理实验在培养学生创新能力和综合实践能力方面发挥应有的作用。     

基于β-二亚胺配体的铝氧硼六元环化合物和其中间体的合成、表征及其反应性研究

LAl H2(L=(Z)-4-[(2,6-二异丙基苯基)氨基]戊-3-烯-2-亚基-2,6-二异丙基苯胺)分别与2-噻吩苯硼酸和2-苯并噻吩硼酸反应,合成含铝氧硼六元环的化合物LAl[OB(2-thiophen)]2(μ-O)(2)和LAl[OB(2-benzo[b]thiophen)]2(μ-O)(3)。LAl H2与2,6-二甲基苯硼酸反应生成了LAl[OB(2,6-CH3C6H4)OH]2(4)。化合物4是化合物2和3的中间体。所有化合物都进行了IR、1H NMR和元素分析等表征。并通过X射线单晶衍射测定了化合物2和4的单晶结构。     

高温吸热管内超临界CO2传热特性的数值模拟

研究超临界CO2在高温吸热管内的传热特性是将其应用于聚光太阳能热发电技术中的基础.本文对此进行了数值模拟研究,分析了流体温度、流动方向、系统压力、质量流率和热流密度对对流传热系数和Nu数的影响.结果表明:高温区(800—1050 K)的对流传热系数和Nu数受流动方向和系统压力的影响均很小,但都随着质量流率的增大以及热流密度的减小而明显增大;而随着流体温度的升高,对流传热系数近似线性增大,Nu数则近似线性减小.另外,本文研究发现在高温区可忽略浮升力对传热的影响,而由高热流密度引起的流动加速效应会明显恶化传热.最后,选取了八种管内超临界流体传热关联式与模拟结果进行对比,发现使用基于热物性修正的关联式对高温区传热数据预测的结果优于使用基于无量纲数修正的关联式得到的结果,且其中预测效果最优的关联式得到的计算结果与模拟结果之间的平均绝对相对偏差为8.1%.     

Syntheses and Crystal Structures of Two Tin(Ⅳ) Complexes with Aminosilane Bearing Ligand

Aminosilane bearing bulky substituents on nitrogen: LH2(L=Me2Si(NDipp-)2 , Dipp=2,6-diisopropylphenyl) was reacted with BuLi in toluene. The resulting bulky chelating dianion Me2Si(NDipp-)2 was used to synthesize the unusual spirocyclic heterotriatomic complex [Me2Si(NDipp)2]2Sn (1) by its reaction with SnCl4 and the bulky heterotriatomic complex Me2Si(NDipp)2SnPh2 (2) with Ph2SnCl2.1 belongs to the monoclinic system, space group P21/n with a=13.193(2), b=20.663(3), c=20.403(3), β=99.954(2)o, V=5478.3(15)3 , C55H85.5N4Si2Sn, Mr=977.64, Z=4, Dc=1.185Mg/m3 , μ(MoKα)=0.547mm-1 , F(000)=2086, S=1.000, the final R=0.0614 and wR=0.1322 for 14446 observed reflections (I2σ(I)) and R=0.0797 and wR=0.1456 for all data. 2 belongs to the triclinic system, space group Pī with a=10.36(15), b=13.204(7), c=14.363(7), α=90.214(10), β=106.182(7), γ=109.854(8)o, V=1764.4(15)3 , C38H50N2SiSn, Mr=681.58, Z=2, Dc=1.283 Mg/m3 , μ(MoKα)=0.785 mm-1 , F(000)=712, S=1.002, the final R=0.0498 and wR=0.0955 for 7533 observed reflections (I2σ(I)) and R=0.0676 and wR=0.1018 for all data. In the structure of 1, the tin atom is located in the spirocyclic center of the two fused four-membered SnN 2 Si rings. The two complexes were characterized by 1H NMR, elemental analysis, and single-crystal X-ray structural analysis.     

电子信息类卓越工程师培养模式探讨

根据国家培养卓越工程师的要求,探讨了电子信息类卓越工程师的培养标准与内容,提出了校企深度合作培养卓越工程师的模式.从低年级学生中选拔有学习激情、自学能力强、善于思考的优秀本科生组成卓越工程师班,在信息学科校企卓越工程师培养教学指导委员会指导下,制定拔尖人才培养方案,加强学生的实践和创新能力培养,采用"3+1"的校企培养模式并通过学科竞赛等手段,使学生在保证学科基础理论学习的同时,突出工程师实践能力的培养,充分发挥学生的主观能动性,培养学生创新能力和独立分析问题、解决问题的能力,从而达到学以致用并完成卓越工程师的基本训练.     

Li-Yorke敏感的乘积性和复合性

讨论Li-Yorke敏感的乘积性质以及它的迭代不变性.主要证明了Li-Yorke敏感在乘积运算下是保持的,以及在一致连续意义下,它的复合运算也是保持的.同时,举例说明该结论对于一般的连续自映射不成立.     

校企合作培养卓越软件工程师模式的探索与实践

基于企业对计算机应用型人才的需求,以及独立学院计算机专业人才培养的特点,探索了一种实用的依托校企合作培养卓越软件工程师的模式:兼顾学生、学校与企业三方面的需求,以"强能力、以就业为导向"作为核心,依托校企合作共建的实验室与实习基地,采用"2+1+1"的模块化教学模式,逐步培养适合企业需求的卓越软件工程师.该模式经过两年多的实践运行,学生的学习积极性、理论应用能力与动手能力迅速提高,计算机专业的教学效果得到了很好的改善.